Software Engineer - Wallets

Responsibilities

• Own the architecture of Rain’s custodial and non-custodial wallet infrastructure.
• Design flexible signing infrastructure supporting MPC, HSMs, secure enclaves, TEEs, and emerging cryptographic approaches.
• Build wallet systems supporting EOAs, smart contract wallets, account abstraction, ERC-4337, embedded wallets, and multichain infrastructure.
• Architect key-management systems for generation, distributed generation, storage, rotation, backup, recovery, and hardware-backed isolation.
• Build highly available signing and transaction infrastructure with reliable developer-facing APIs.
• Set technical direction for wallet security, threat modeling, policy engines, secrets management, account recovery, authentication, and programmable authorization.
• Make build-versus-buy and other foundational architecture decisions across cryptography, custody, wallet, and security infrastructure.

Requirements

• Deep expertise in wallet, custody, cryptography, or security infrastructure, along with strong distributed-systems and architecture fundamentals.
• Production experience designing or building wallet, custody, signing, or key-management systems that secure high-value assets.
• Knowledge of applied cryptography, including MPC, threshold cryptography, threshold signatures, distributed key generation, ECDSA, EdDSA, or secure multiparty computation.
• Experience with HSMs, secure enclaves, TEEs, confidential computing, hardware-backed key isolation, or comparable security-critical infrastructure.
• Understanding of wallet and blockchain account architecture, including EOAs, smart contract wallets, account abstraction, ERC-4337, transaction orchestration, and multichain systems.
• Experience designing authentication, authorization, policy, permissions, recovery, or secrets-management systems where security and correctness are critical.
• Track record of making architectural decisions in complex distributed systems and evaluating security, reliability, developer-experience, and extensibility tradeoffs.
• Ability to communicate technical tradeoffs, form strong technical opinions, and own architecture from first principles through production.

Benefits

• Unlimited time off with a required minimum of 10 days taken annually.
• Flexible work arrangement allowing employees to work from home, in an office, or in a combination of both.
• Home-workspace setup stipend for new employees.
• For US employees, Rain covers 95% of employee health, dental, and vision costs and 90% for dependents, plus fully subsidized life insurance.
• 401(k) plan with a 4% company match.
• Equity option plan for every employee.
• Monthly health and wellness stipend.
• Free lunch and dinner for employees working from the office through DoorDash credit.
• Domestic and international team and company offsites.